Пример #1
0
        /// <summary>
        /// Returns the max value for the specified metadata kind.
        /// The metadata type should be a KeyType with raw type U4.
        /// colMax will be set to the first column that has the max value for the specified metadata.
        /// If no column has the specified metadata, colMax is set to -1 and the method returns zero.
        /// The filter function is called for each column, passing in the schema and the column index, and returns
        /// true if the column should be considered, false if the column should be skipped.
        /// </summary>
        public static uint GetMaxMetadataKind(this ISchema schema, out int colMax, string metadataKind, Func <ISchema, int, bool> filterFunc = null)
        {
            uint max = 0;

            colMax = -1;
            for (int col = 0; col < schema.ColumnCount; col++)
            {
                var columnType = schema.GetMetadataTypeOrNull(metadataKind, col);
                if (columnType == null || !columnType.IsKey || columnType.RawKind != DataKind.U4)
                {
                    continue;
                }
                if (filterFunc != null && !filterFunc(schema, col))
                {
                    continue;
                }
                uint value = 0;
                schema.GetMetadata(metadataKind, col, ref value);
                if (max < value)
                {
                    max    = value;
                    colMax = col;
                }
            }
            return(max);
        }
Пример #2
0
        /// <summary>
        /// This is a utility method used to determine whether <see cref="LabelNameBindableMapper"/>
        /// can or should be used to wrap <paramref name="mapper"/>. This will not throw, since the
        /// desired behavior in the event that it cannot be wrapped, is to just back off to the original
        /// "unwrapped" bound mapper.
        /// </summary>
        /// <param name="mapper">The mapper we are seeing if we can wrap</param>
        /// <param name="labelNameType">The type of the label names from the metadata (either
        /// originating from the key value metadata of the training label column, or deserialized
        /// from the model of a bindable mapper)</param>
        /// <returns>Whether we can call <see cref="LabelNameBindableMapper.CreateBound{T}"/> with
        /// this mapper and expect it to succeed</returns>
        public static bool CanWrap(ISchemaBoundMapper mapper, ColumnType labelNameType)
        {
            Contracts.AssertValue(mapper);
            Contracts.AssertValue(labelNameType);

            ISchemaBoundRowMapper rowMapper = mapper as ISchemaBoundRowMapper;

            if (rowMapper == null)
            {
                return(false); // We could cover this case, but it is of no practical worth as far as I see, so I decline to do so.
            }
            ISchema outSchema = mapper.Schema;
            int     scoreIdx;

            if (!outSchema.TryGetColumnIndex(MetadataUtils.Const.ScoreValueKind.Score, out scoreIdx))
            {
                return(false); // The mapper doesn't even publish a score column to attach the metadata to.
            }
            if (outSchema.GetMetadataTypeOrNull(MetadataUtils.Kinds.SlotNames, scoreIdx) != null)
            {
                return(false); // The mapper publishes a score column, and already produces its own slot names.
            }
            var scoreType = outSchema.GetColumnType(scoreIdx);

            // Check that the type is vector, and is of compatible size with the score output.
            return(labelNameType.IsVector && labelNameType.VectorSize == scoreType.VectorSize);
        }
Пример #3
0
            // Computes the types of the columns and constructs the kvMaps.
            private void ComputeKvMaps(ISchema schema, out ColumnType[] types, out KeyToValueMap[] kvMaps)
            {
                types  = new ColumnType[_parent.ColumnPairs.Length];
                kvMaps = new KeyToValueMap[_parent.ColumnPairs.Length];
                for (int iinfo = 0; iinfo < types.Length; iinfo++)
                {
                    // Construct kvMaps.
                    Contracts.Assert(types[iinfo] == null);
                    var typeSrc  = schema.GetColumnType(ColMapNewToOld[iinfo]);
                    var typeVals = schema.GetMetadataTypeOrNull(MetadataUtils.Kinds.KeyValues, ColMapNewToOld[iinfo]);
                    Host.Check(typeVals != null, "Metadata KeyValues does not exist");
                    Host.Check(typeVals.VectorSize == typeSrc.ItemType.KeyCount, "KeyValues metadata size does not match column type key count");
                    if (!typeSrc.IsVector)
                    {
                        types[iinfo] = typeVals.ItemType;
                    }
                    else
                    {
                        types[iinfo] = new VectorType(typeVals.ItemType.AsPrimitive, typeSrc.AsVector);
                    }

                    // MarshalInvoke with two generic params.
                    Func <int, ColumnType, ColumnType, KeyToValueMap> func = GetKeyMetadata <int, int>;
                    var meth = func.GetMethodInfo().GetGenericMethodDefinition().MakeGenericMethod(
                        new Type[] { typeSrc.ItemType.RawType, types[iinfo].ItemType.RawType });
                    kvMaps[iinfo] = (KeyToValueMap)meth.Invoke(this, new object[] { iinfo, typeSrc, typeVals });
                }
            }
        // Computes the column type and whether multiple indicator vectors need to be concatenated.
        // Also populates the metadata.
        private static void ComputeType(KeyToVectorTransform trans, ISchema input, int iinfo, ColInfo info, bool bag,
                                        MetadataDispatcher md, out VectorType type, out bool concat)
        {
            Contracts.AssertValue(trans);
            Contracts.AssertValue(input);
            Contracts.AssertValue(info);
            Contracts.Assert(info.TypeSrc.ItemType.IsKey);
            Contracts.AssertValue(md);

            int size = info.TypeSrc.ItemType.KeyCount;

            Contracts.Assert(size > 0);

            // See if the source has key names.
            var typeNames = input.GetMetadataTypeOrNull(MetadataUtils.Kinds.KeyValues, info.Source);

            if (typeNames == null || !typeNames.IsKnownSizeVector || !typeNames.ItemType.IsText ||
                typeNames.VectorSize != size)
            {
                typeNames = null;
            }

            // Don't pass through any source column metadata.
            using (var bldr = md.BuildMetadata(iinfo))
            {
                if (bag || info.TypeSrc.ValueCount == 1)
                {
                    // Output is a single vector computed as the sum of the output indicator vectors.
                    concat = false;
                    type   = new VectorType(NumberType.Float, size);
                    if (typeNames != null)
                    {
                        bldr.AddGetter <VBuffer <DvText> >(MetadataUtils.Kinds.SlotNames, typeNames, trans.GetKeyNames);
                    }
                }
                else
                {
                    // Output is the concatenation of the multiple output indicator vectors.
                    concat = true;
                    type   = new VectorType(NumberType.Float, info.TypeSrc.ValueCount, size);
                    if (typeNames != null && type.VectorSize > 0)
                    {
                        bldr.AddGetter <VBuffer <DvText> >(MetadataUtils.Kinds.SlotNames,
                                                           new VectorType(TextType.Instance, type), trans.GetSlotNames);
                    }
                }

                if (!bag && info.TypeSrc.ValueCount > 0)
                {
                    bldr.AddGetter <VBuffer <DvInt4> >(MetadataUtils.Kinds.CategoricalSlotRanges,
                                                       MetadataUtils.GetCategoricalType(info.TypeSrc.ValueCount), trans.GetCategoricalSlotRanges);
                }

                if (!bag || info.TypeSrc.ValueCount == 1)
                {
                    bldr.AddPrimitive(MetadataUtils.Kinds.IsNormalized, BoolType.Instance, DvBool.True);
                }
            }
        }
Пример #5
0
 public ColumnType GetMetadataTypeOrNull(string kind, int col)
 {
     if (col == _col && kind == MetadataUtils.Kinds.SlotNames)
     {
         return(_type);
     }
     return(_parent.GetMetadataTypeOrNull(kind, col));
 }
Пример #6
0
 public ColumnType GetMetadataTypeOrNull(string kind, int col)
 {
     if (col == _scoreCol && kind == _metadataKind)
     {
         return(_labelNameType);
     }
     return(_parent.GetMetadataTypeOrNull(kind, col));
 }
Пример #7
0
 public ColumnType GetMetadataTypeOrNull(string kind, int col)
 {
     _ectx.Check(0 <= col && col < ColumnCount);
     if (IsPivot(col) && !ShouldPreserveMetadata(kind))
     {
         return(null);
     }
     return(_inputSchema.GetMetadataTypeOrNull(kind, col));
 }
Пример #8
0
        public DataViewType GetMetadataTypeOrNull(string kind, int col)
        {
            int count = _schemaInput.ColumnCount;

            if (col < count)
            {
                return(_schemaInput.GetMetadataTypeOrNull(kind, col));
            }
            return(null);
        }
Пример #9
0
        /// <summary>
        /// Tries to get the metadata kind of the specified type for a column.
        /// </summary>
        /// <typeparam name="T">The raw type of the metadata, should match the PrimitiveType type</typeparam>
        /// <param name="schema">The schema</param>
        /// <param name="type">The type of the metadata</param>
        /// <param name="kind">The metadata kind</param>
        /// <param name="col">The column</param>
        /// <param name="value">The value to return, if successful</param>
        /// <returns>True if the metadata of the right type exists, false otherwise</returns>
        public static bool TryGetMetadata <T>(this ISchema schema, PrimitiveType type, string kind, int col, ref T value)
        {
            var metadataType = schema.GetMetadataTypeOrNull(kind, col);

            if (!type.Equals(metadataType))
            {
                return(false);
            }
            schema.GetMetadata(kind, col, ref value);
            return(true);
        }
        /// <summary>
        /// Computes the column type and whether multiple indicator vectors need to be concatenated.
        /// Also populates the metadata.
        /// </summary>
        private static void ComputeType(KeyToBinaryVectorTransform trans, ISchema input, int iinfo,
                                        ColInfo info, MetadataDispatcher md, out VectorType type, out bool concat, out int bitsPerColumn)
        {
            Contracts.AssertValue(trans);
            Contracts.AssertValue(input);
            Contracts.AssertValue(info);
            Contracts.Assert(info.TypeSrc.ItemType.IsKey);
            Contracts.Assert(info.TypeSrc.ItemType.KeyCount > 0);

            //Add an additional bit for all 1s to represent missing values.
            bitsPerColumn = Utils.IbitHigh((uint)info.TypeSrc.ItemType.KeyCount) + 2;

            Contracts.Assert(bitsPerColumn > 0);

            // See if the source has key names.
            var typeNames = input.GetMetadataTypeOrNull(MetadataUtils.Kinds.KeyValues, info.Source);

            if (typeNames == null || !typeNames.IsKnownSizeVector || !typeNames.ItemType.IsText ||
                typeNames.VectorSize != info.TypeSrc.ItemType.KeyCount)
            {
                typeNames = null;
            }

            // Don't pass through any source column metadata.
            using (var bldr = md.BuildMetadata(iinfo))
            {
                if (info.TypeSrc.ValueCount == 1)
                {
                    // Output is a single vector computed as the sum of the output indicator vectors.
                    concat = false;
                    type   = new VectorType(NumberType.Float, bitsPerColumn);
                    if (typeNames != null)
                    {
                        bldr.AddGetter <VBuffer <DvText> >(MetadataUtils.Kinds.SlotNames,
                                                           new VectorType(TextType.Instance, type), trans.GetKeyNames);
                    }

                    bldr.AddPrimitive(MetadataUtils.Kinds.IsNormalized, BoolType.Instance, DvBool.True);
                }
                else
                {
                    // Output is the concatenation of the multiple output indicator vectors.
                    concat = true;
                    type   = new VectorType(NumberType.Float, info.TypeSrc.ValueCount, bitsPerColumn);
                    if (typeNames != null && type.VectorSize > 0)
                    {
                        bldr.AddGetter <VBuffer <DvText> >(MetadataUtils.Kinds.SlotNames,
                                                           new VectorType(TextType.Instance, type), trans.GetSlotNames);
                    }
                }
            }
        }
Пример #11
0
            private static IColumn KeyValueMetadataFromMetadata <T>(ISchema schema, int col, string metadataName)
            {
                Contracts.AssertValue(schema);
                Contracts.Assert(0 <= col && col < schema.ColumnCount);
                var type = schema.GetMetadataTypeOrNull(metadataName, col);

                Contracts.AssertValue(type);
                Contracts.Assert(type.RawType == typeof(T));

                ValueGetter <T> getter = (ref T val) => schema.GetMetadata(metadataName, col, ref val);

                return(RowColumnUtils.GetColumn(MetadataUtils.Kinds.KeyValues, type, getter));
            }
            public IEnumerable <KeyValuePair <string, ColumnType> > GetMetadataTypes(int col)
            {
                CheckColumnInRange(col);
                if (col < _groupCount)
                {
                    return(_input.GetMetadataTypes(GroupIds[col]));
                }

                col -= _groupCount;
                var result = new List <KeyValuePair <string, ColumnType> >();

                foreach (var kind in _preservedMetadata)
                {
                    var colType = _input.GetMetadataTypeOrNull(kind, KeepIds[col]);
                    if (colType != null)
                    {
                        result.Add(colType.GetPair(kind));
                    }
                }

                return(result);
            }
Пример #13
0
        /// <summary>
        /// Tries to get the metadata kind of the specified type for a column.
        /// </summary>
        /// <typeparam name="T">The raw type of the metadata, should match the PrimitiveType type</typeparam>
        /// <param name="schema">The schema</param>
        /// <param name="type">The type of the metadata</param>
        /// <param name="kind">The metadata kind</param>
        /// <param name="col">The column</param>
        /// <param name="value">The value to return, if successful</param>
        /// <returns>True if the metadata of the right type exists, false otherwise</returns>
        public static bool TryGetMetadata <T>(this ISchema schema, PrimitiveType type, string kind, int col, ref T value)
        {
            Contracts.CheckValue(schema, nameof(schema));
            Contracts.CheckValue(type, nameof(type));

            var metadataType = schema.GetMetadataTypeOrNull(kind, col);

            if (!type.Equals(metadataType))
            {
                return(false);
            }
            schema.GetMetadata(kind, col, ref value);
            return(true);
        }
        public ColumnType GetMetadataTypeOrNull(string kind, int col)
        {
            Contracts.CheckNonEmpty(kind, nameof(kind));
            Contracts.CheckParam(0 <= col && col < ColumnCount, nameof(col));

            bool isSrc;
            int  index = MapColumnIndex(out isSrc, col);

            if (isSrc)
            {
                return(Input.GetMetadataTypeOrNull(kind, index));
            }
            Contracts.Assert(0 <= index && index < InfoCount);
            return(GetMetadataTypeCore(kind, index));
        }
Пример #15
0
        public static bool HasKeyNames(this ISchema schema, int col, int keyCount)
        {
            if (keyCount == 0)
            {
                return(false);
            }

            var type = schema.GetMetadataTypeOrNull(Kinds.KeyValues, col);

            return
                (type != null &&
                 type.IsVector &&
                 type.VectorSize == keyCount &&
                 type.ItemType.IsText);
        }
Пример #16
0
        /// <summary>
        /// Returns <c>true</c> if the specified column:
        ///  * is a vector of length N (including 0)
        ///  * has a SlotNames metadata
        ///  * metadata type is VBuffer&lt;ReadOnlyMemory&lt;char&gt;&gt; of length N
        /// </summary>
        public static bool HasSlotNames(this ISchema schema, int col, int vectorSize)
        {
            if (vectorSize == 0)
            {
                return(false);
            }

            var type = schema.GetMetadataTypeOrNull(Kinds.SlotNames, col);

            return
                (type != null &&
                 type.IsVector &&
                 type.VectorSize == vectorSize &&
                 type.ItemType.IsText);
        }
Пример #17
0
 /// <summary>
 /// Returns the set of column ids which match the value of specified metadata kind.
 /// The metadata type should be of type text.
 /// </summary>
 public static IEnumerable <int> GetColumnSet(this ISchema schema, string metadataKind, string value)
 {
     for (int col = 0; col < schema.ColumnCount; col++)
     {
         var columnType = schema.GetMetadataTypeOrNull(metadataKind, col);
         if (columnType != null && columnType.IsText)
         {
             ReadOnlyMemory <char> val = default;
             schema.GetMetadata(metadataKind, col, ref val);
             if (ReadOnlyMemoryUtils.EqualsStr(value, val))
             {
                 yield return(col);
             }
         }
     }
 }
Пример #18
0
 /// <summary>
 /// Returns the set of column ids which match the value of specified metadata kind.
 /// The metadata type should be a KeyType with raw type U4.
 /// </summary>
 public static IEnumerable <int> GetColumnSet(this ISchema schema, string metadataKind, uint value)
 {
     for (int col = 0; col < schema.ColumnCount; col++)
     {
         var columnType = schema.GetMetadataTypeOrNull(metadataKind, col);
         if (columnType != null && columnType.IsKey && columnType.RawKind == DataKind.U4)
         {
             uint val = 0;
             schema.GetMetadata(metadataKind, col, ref val);
             if (val == value)
             {
                 yield return(col);
             }
         }
     }
 }
Пример #19
0
        /// <summary>
        /// The categoricalFeatures is a vector of the indices of categorical features slots.
        /// This vector should always have an even number of elements, and the elements should be parsed in groups of two consecutive numbers.
        /// So if its value is the range of numbers: 0,2,3,4,8,9
        /// look at it as [0,2],[3,4],[8,9].
        /// The way to interpret that is: feature with indices 0, 1, and 2 are one categorical
        /// Features with indices 3 and 4 are another categorical. Features 5 and 6 don't appear there, so they are not categoricals.
        /// </summary>
        public static bool TryGetCategoricalFeatureIndices(ISchema schema, int colIndex, out int[] categoricalFeatures)
        {
            Contracts.CheckValue(schema, nameof(schema));
            Contracts.Check(colIndex >= 0, nameof(colIndex));

            bool isValid = false;

            categoricalFeatures = null;
            if (!schema.GetColumnType(colIndex).IsKnownSizeVector)
            {
                return(isValid);
            }

            var type = schema.GetMetadataTypeOrNull(MetadataUtils.Kinds.CategoricalSlotRanges, colIndex);

            if (type?.RawType == typeof(VBuffer <int>))
            {
                VBuffer <int> catIndices = default(VBuffer <int>);
                schema.GetMetadata(MetadataUtils.Kinds.CategoricalSlotRanges, colIndex, ref catIndices);
                VBufferUtils.Densify(ref catIndices);
                int columnSlotsCount = schema.GetColumnType(colIndex).AsVector.VectorSizeCore;
                if (catIndices.Length > 0 && catIndices.Length % 2 == 0 && catIndices.Length <= columnSlotsCount * 2)
                {
                    int previousEndIndex = -1;
                    isValid = true;
                    for (int i = 0; i < catIndices.Values.Length; i += 2)
                    {
                        if (catIndices.Values[i] > catIndices.Values[i + 1] ||
                            catIndices.Values[i] <= previousEndIndex ||
                            catIndices.Values[i] >= columnSlotsCount ||
                            catIndices.Values[i + 1] >= columnSlotsCount)
                        {
                            isValid = false;
                            break;
                        }

                        previousEndIndex = catIndices.Values[i + 1];
                    }
                    if (isValid)
                    {
                        categoricalFeatures = catIndices.Values.Select(val => val).ToArray();
                    }
                }
            }

            return(isValid);
        }
Пример #20
0
                    public SchemaImpl(ISchema parent, int col, VectorType type, ValueGetter <VBuffer <T> > getter, string metadataKind)
                    {
                        Contracts.AssertValue(parent);
                        Contracts.Assert(0 <= col && col < parent.ColumnCount);
                        Contracts.AssertValue(type);
                        Contracts.AssertValue(getter);
                        Contracts.Assert(type.ItemType.RawType == typeof(T));
                        Contracts.AssertNonEmpty(metadataKind);
                        Contracts.Assert(parent.GetMetadataTypeOrNull(metadataKind, col) == null);

                        _parent        = parent;
                        _scoreCol      = col;
                        _labelNameType = type;
                        // We change to this metadata variant of the getter to enable the marshal call to work.
                        _labelNameGetter = (int c, ref VBuffer <T> val) => getter(ref val);
                        _metadataKind    = metadataKind;
                    }
Пример #21
0
        /// <summary>
        /// Returns the metadata.
        /// </summary>
        public ColumnType GetMetadataTypeOrNull(string kind, int col)
        {
            int count = _schemaInput == null ? 0 : _schemaInput.ColumnCount;

            if (col < count)
            {
                return(_schemaInput.GetMetadataTypeOrNull(kind, col));
            }
            if (kind == MetadataUtils.Kinds.SlotNames)
            {
                var ty = GetColumnType(col);
                if (ty.IsVector() && ty.AsVector().DimCount() == 1 && ty.AsVector().GetDim(0) > 0)
                {
                    return(new VectorType(TextType.Instance, ty.AsVector().GetDim(0)));
                }
            }
            return(null);
        }
Пример #22
0
        private ValueGetter <VBuffer <ReadOnlyMemory <char> > > CreateSlotNamesGetter(ISchema schema, int column, int length, string prefix)
        {
            var type = schema.GetMetadataTypeOrNull(MetadataUtils.Kinds.SlotNames, column);

            if (type != null && type.IsText)
            {
                return
                    ((ref VBuffer <ReadOnlyMemory <char> > dst) => schema.GetMetadata(MetadataUtils.Kinds.SlotNames, column, ref dst));
            }
            return
                ((ref VBuffer <ReadOnlyMemory <char> > dst) =>
            {
                var values = dst.Values;
                if (Utils.Size(values) < length)
                {
                    values = new ReadOnlyMemory <char> [length];
                }
                for (int i = 0; i < length; i++)
                {
                    values[i] = string.Format("{0}_{1}", prefix, i).AsMemory();
                }
                dst = new VBuffer <ReadOnlyMemory <char> >(length, values);
            });
        }
        private MetadataUtils.MetadataGetter <VBuffer <DvText> > CreateSlotNamesGetter(ISchema schema, int column, int length, string prefix)
        {
            var type = schema.GetMetadataTypeOrNull(MetadataUtils.Kinds.SlotNames, column);

            if (type != null && type.IsText)
            {
                return
                    ((int col, ref VBuffer <DvText> dst) => schema.GetMetadata(MetadataUtils.Kinds.SlotNames, column, ref dst));
            }
            return
                ((int col, ref VBuffer <DvText> dst) =>
            {
                var values = dst.Values;
                if (Utils.Size(values) < length)
                {
                    values = new DvText[length];
                }
                for (int i = 0; i < length; i++)
                {
                    values[i] = new DvText(string.Format("{0}_{1}", prefix, i));
                }
                dst = new VBuffer <DvText>(length, values);
            });
        }
Пример #24
0
 public ColumnType GetMetadataTypeOrNull(string kind, int col)
 {
     Contracts.CheckNonEmpty(kind, nameof(kind));
     Contracts.CheckParam(0 <= col && col < ColumnCount, nameof(col));
     return(Input.GetMetadataTypeOrNull(kind, ColMap[col]));
 }
Пример #25
0
        private static void PrintSchema(TextWriter writer, Arguments args, ISchema schema, ITransposeSchema tschema)
        {
            Contracts.AssertValue(writer);
            Contracts.AssertValue(args);
            Contracts.AssertValue(schema);
            Contracts.AssertValueOrNull(tschema);
#if !CORECLR
            if (args.ShowJson)
            {
                writer.WriteLine("Json Schema not supported.");
                return;
            }
#endif
            int colLim = schema.ColumnCount;
            writer.WriteLine("{0} columns:", colLim);

            var itw = IndentingTextWriter.Wrap(writer);
            using (itw.Nest())
            {
                var names = default(VBuffer <ReadOnlyMemory <char> >);
                for (int col = 0; col < colLim; col++)
                {
                    var name     = schema.GetColumnName(col);
                    var type     = schema.GetColumnType(col);
                    var slotType = tschema == null ? null : tschema.GetSlotType(col);
                    itw.WriteLine("{0}: {1}{2}", name, type, slotType == null ? "" : " (T)");

                    bool metaVals = args.ShowMetadataValues;
                    if (metaVals || args.ShowMetadataTypes)
                    {
                        ShowMetadata(itw, schema, col, metaVals);
                        continue;
                    }

                    if (!args.ShowSlots)
                    {
                        continue;
                    }
                    if (!type.IsKnownSizeVector)
                    {
                        continue;
                    }
                    ColumnType typeNames;
                    if ((typeNames = schema.GetMetadataTypeOrNull(MetadataUtils.Kinds.SlotNames, col)) == null)
                    {
                        continue;
                    }
                    if (typeNames.VectorSize != type.VectorSize || !typeNames.ItemType.IsText)
                    {
                        Contracts.Assert(false, "Unexpected slot names type");
                        continue;
                    }
                    schema.GetMetadata(MetadataUtils.Kinds.SlotNames, col, ref names);
                    if (names.Length != type.VectorSize)
                    {
                        Contracts.Assert(false, "Unexpected length of slot names vector");
                        continue;
                    }

                    using (itw.Nest())
                    {
                        bool verbose = args.Verbose ?? false;
                        foreach (var kvp in names.Items(all: verbose))
                        {
                            if (verbose || !kvp.Value.IsEmpty)
                            {
                                itw.WriteLine("{0}:{1}", kvp.Key, kvp.Value);
                            }
                        }
                    }
                }
            }
        }
 public ColumnType GetMetadataTypeOrNull(string kind, int col)
 {
     return(_schema.GetMetadataTypeOrNull(kind, _revmapping[col]));
 }